Vibration damper

[Pierre Michaud]

The following was taken from an auto web page which may interest owners of R69S's....at least explain part of the theory behind the vibration damper!

Harmonic Balancer

When a cylinder fires, the piston produces a torsional force on the crankshaft. It also produces
vibration. The vibrations produced by the running engine tend to concentrate at the ends of the
crankshaft. At the rear, these are absorbed by the flywheel and drive train. At the front, it is the job of the harmonic balancer to damp the vibration. The balancer consists of a hub, surrounded by dense
rubber, surrounded by a heavy metal ring.

Designing a harmonic balancer is almost a black art. The design is dependent on reciprocating weight,engine design and target peak rpm. Theory only accounts for part of the design. In a running engine,lubricants can cling unevenly to the motion work, causing unpredictable variations from expected results. The combination of the correct density rubber, and the right weight outer ring will either work or not.

There are a number of high performance balancers available for the XK engine. I am thinking that it would not be a bad idea to pop one on. Supposedly a good balancer will allow you to rev to 7000 rpm. Then again, I'm trying to get my revs down.....hmmmm.

[J. Stracco]

Pierre-

What's the URL? And are any of the dampers adaptable to a /2?

[Pierre Michaud]

Sorry John, I lost it. It was an automobile URL.

[Pierre Michaud]

John,

You can find all sorts of stuff by using HARMONIC+DAMPER. Here is one from Australia http://home.earthlink.net/~prorace/damp ... nsions.htm

These dampers are pretty big, over 6.5" diameter. They have a nice feature in that the elastomer is encased in the steel puck!

If you find anything interesting for /2's let me know....perhaps they would be interested in making one for the /2's if they had volume!